Mold press



July 4, 1933.

P. o. GUNKEL 1,916,368

MOLD PRESS Filed NOV. 6, 1929 3 Sheets-Sheet l July 4, 1933.

Filed Nov. 6, 1929 3 Sheets-Sheet 2 w W yd, 9 mfi a Q 4/, h M.

P. O. GUNKEL July 4, 1933.

MOLD PRESS Filed Nov. 6, 1929 3 Sheets-Sheet 3 Fatentccl July 4, 1933 was rates ra'ru'r orrica PAUL O. GUNKEL, OF WELLAND, OI-TTAREO, CA1\ ADA, ASSIGNOE TO JOSEPH STOKES RUBBER OGMPANY, 0F TRENTOII, NEW JERSEY, A CORIEOBATIOII OF NEW JERSEY.

MOLD ranss Application filed'ficvember 6,1929. Serial No. 405,221.

ing the mold plates to operative position after the molded article'has been removed from the mold. a Other objects and features of novelty will appear as I proceedwith the description of that embodiment of the invention which, for

the purposes of the present application, I have illustrated in the accompanying drawings, in which Figure '1 is a front elevational view of a press embodying my invention, with certain parts broken away and others shown in section in order to more fully illustrate the invention. i 2

Fig.2 is a side elevational view of the same. I Fig. 3 is a fragmental vertical sectional view showing certain portions of the apparatus upon an enlarged scale and in a different operative position. Fig. 4 is a plan view of the mold frame with the mold plates in position therein.

'Fig. 5 is a vertical sectional view taken substantially on theline 5-5of Fig. 4.

Fig. 6 is a view on a larger scale corresponding to the lower part of Fig.2, with certain parts shown in section, and

Fig. 7 is a diagrammatic view showing fluid connections to the shock absorbing cylinders. W

In the drawings I have illustrated a press of more or less conventional form 'comprising four columns 10 connected at their upper ends by a headll. In the latter, and

preferably cast integral therewith, is a main 'a core plate 30 and core 31, the latter being cylinder 12 which may be opened either to the pressure fluid line or toeXhaust byvalve means, not shown. Within the cylinder'12 is a ram 13 which is attached to a platen 14 10 A short distance above the bottom of the columns there is mounted a stationary table 15.

Supported upon the head 11, and extending upwardly fromthe outer sides thereof, are two cylinders 16 of relatively small diameter which are always in connection with the pressure fluid line. Plungers 17 cooperate therewith and carry at their upper extremities cross heads 18, on the outer ends of which are connected rods 19. The lower ends of the latter are attached to the platen 14. Because of its relatively large capacity the admission of pressure fluid to cylinder 12 serves to depress the platen 14 against the action of pressure fluid in cylinder 16, but whenever cylinder 12 is open to exhaust the plungers 17 rise and elevate the platen 14.

As shown in Fi s. 1 and 5 I mount upon the table 15 a mold frame 20, and affix it to the.

table by any suitable means such as by studs 21 extending through lugs 22 on the frame. The inner walls of this frame are inclined upwardly and outwardly, as shown in Fig. 5, and are provided with T- grooves 23 extending from top. to bottom of the frame. bottom mold plate 24 rests normally upon the table 15 within the frame 20. It has a horizontal groove 25 extending entirely around its periphery. Into this groove ex+ tend lips 26 which are integral with'each of the side plates 27, 28 of the mold, providing an inter-engagement which is maintained throughout the vertical movement of the.

centered with respect to the mold. In order to insure proper registry,fthe core plate is provided with depending dowels 32 which take into holes 33 in the mold frame 20.

The bottom plate 24 of the mold is threaded too upon the reduced end of a post 34, which is slidable through an opening in the table 15 and is secured at its lower end to a cross head 35. At its outer ends this cross head is supported by pairs of spaced rods 36, which extend upwardly through guide holes in the table 15 and through further guide holes in a portion 37 of the platen 14. At their upper ends the rods of each pair are connected vby a bar 38. Upon a horizontal pivot 39 carried by the platen 14 I mount a trigger 40 in the form of a bell crank lever, the upstanding arm of which is adapted to take under the bar 38, as indicated in Fig. 3, in order to raise that bar as the platen 14 travels upwardly. The trigger 40 is urged toward the position of Fig. 3 by means of a spring 41. On'the laterally extending arm of the trigger 40 there'is a pro ection 42 which 15 adapted to engage with a tripper pin43 that depends from a bracket 44 on the head 11 and is re:

ceived and guided in a bore through a bracket 45 that is carried by the platen 14.

A pair of angle brackets 46 attached to the under side of head 11 carry a pintle'47 upon which is pivoted a trip lever 48, the lower end of which is bifurcated so as to straddle trigger 40. This lever is adapted to engage the upper inner corner of bar 38. In its upper end this lever carries a roller 49, and its upperend is urged normally toward the left by coil spring 50. The bracket 45 in platen 14 carries an upwardly extending tripperpin 51, which is guided by a hole in the bracket 44. The upper end of pin 51 is pointed to provide a cam surface for engage ment with the roller 49 so as to swing the latter in a clockwise direction when the platen rises sufliciently to bringabout this action. The mechanism of the trigger 40 and trip lever 48 with their associated parts is employed upon both sides of the machine.

Between the rods 360i each pair the cross head 35 carries a vertical stop rod 52, which is slidable through a hole in'the table 15. To the top of the table at each end thereof there is secured a plate 53 provided with smooth openings through which the rods-36 slide. This platehas also a larger central opening which is threaded to receive the threaded lower end of a cylinder 54 arranged between the rods 36. The rod 52 extends upwardly into this cylinder through an opening in the lower end wall 55, a packing gland 56 and gland nut 57 being provided to prevent leakage of liquid from the cylinder. The upper-end of rod 52 has a reduced extremity upon which is mounted a leather washer 58, locked in position by a metal washer 59, nut 60 and lock nut 61.

The cylinder54 nearits lower end has a port 62 which is in communication with the water conductor 63, the latter being connected withalow pressure water line 64 through a suitable check valve construction which may take the form illustrated diagrammatically in Fig. 7, wherein I have shown a downwardly closing ball check 65 mounted in a partition 66, the latter being provided with by-pass openings 6? of restricted size. With a valve arrangement of this type water is free to flow with relative rapidity upwardly through the check valve, but when the direction of flow is downward the check valve closes and the flow must take place slowly through the restricted openings 67. Of course the size and number of openings 67 maybe varied as desired, and in this manner the speed of motion of the mold on its descent may be controlled as will hereinafter appear.

Operation. Assuming that the parts are in the position'illustrated in Figs. 1, 4 and 5, the moldable material is placed within the mold and pressure fluid is then admitted to the cylinder 12 to drive the ram 13 and the platen 14 downwardly. WVhen the platen has descended far enough the dowels 32 enter the dowel holes 33, bringing the core 31 into exact alignment withthe mold. Further downward motion of the platen causes the core 31 to press the molding material upwardly around the core 31 and into the space between the core and the side plates of the mold. .During the first portion of the descent of the platen the projection 42 moves away from the tripper pin 43 and permits the spring 41 to swing trigger 40 out into the position indicated in Fig. 3. Shortly thereafter the tripper pin 51 descends below the level of roller 49, permitting spring 50 to swing lever 48 to the position illustrated in Fig. 3. This latter movement of lever 48 enables the'latter to engage cross bar 38 to lock it in lowered position.

When the molding operation is finished, the heavypressure exerted between the core and mold plates is relieved by opening the cylinder 12 to exhaust. Immediately thereupon the pressure in cylinders 16, acting through plu'ngers 17, cross heads 18 and rods 19, exerts a pull upwardly upon the core 31, and asthe mold is held in its lowered position-bythe lever-48, this pull separates core 31 from the mold. The upward movement of the platen continues uninterruptedly, and at such speed as the exhausting of the cylinder 12 permits. until thepins 51 come into engagement with the rollers 49 and shift them outwardly'to releasethe trip levers 48 from engagement with the bars 38. Directlv thereafter the triggers 40 engage beneath the bars 38, and the latter with the rods 36, cross head 35 and post 34 beginto move upwardly'with the platen 14. This movement raises the bottom plate 24 ofthe mold and with it the side plates 27 and .28. The latter are guided outwardly by the interengagement of the tongues and grooves 29 and 23,

thereby pulling theside plates away from the mit the operator to remove the molded ar-- molded article. As soon as this upward movement has progressed far enough to perdownward, and on account of the.intcrengagement of the bottom plate with the side plates 27, 28 through the groove and lips 26, the side plates are drawn positively downward upon the inner inclined walls of the frame 20 and back into operative position at the time the plate 24 touches the table 15. As

the mold plates descend, the'rod 52 is carried along with them, but as the cylinders 54 are filled at the time with water or other liquid which blocks the path of the washer 58, and as this liquid can be forced back into the line 64 only through the restricted passages 67, downward travel of the mold plates is made to take place as slowly as conditions may require, and can ofcourse be changed by changing the size or number of passages 67. The apparatus is now in condition for the introduction of a new charge of material into the mold and the repetition of the cycle of movementsabove described. When'the mold plates travel upwardly to release the article molded in the succeeding operation,

.liquid flows readily upward through the check valve and again fills the cylinders 54.

While in the'foregoing description and in the accompanying drawings I have disclosed my invention more or less in detail, I desire it to be understood that such disclosure is primarily fort-he purpose of fully illustrating the invention, and isnot to be construed as amounting to a limitation upon the scope thereof.

Having thus described my invention, I claim:

1. In mechanism of the class described, a bottom mold plate, side mold plates adapted to be moved outwardly in order to clear the molded article, means for raising said bottom and side mold plates with the molded article enclosed therebv, means for automatically releasing said plates from the raising means when the latter has travelled through a predetermined distance, and means for forcing said side plates inwardly into molding position as the plates descend.

2. In mechanism of the class described, a bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof and adapted to open in order to free the molded article, a vertically movable platen, a core de pending therefrom, means for raising said platen to pull said core out of the molded article, and means actuated thereafter by the upward travel of the platen for raising said mold plates and simultaneously causing the mold side plates to open outwardlyin order to permit the removal of the molded article.

T3. In mechanism of the class described, a bottom 'mold'plate,side mold plates interengaging said bottom plate at the edges there of, releasable means for holding said plates in their lower-"position, a vertically movable platen, a. core: depending therefrom, means for raising said platen to pull said core out of the molded article, said platen carrying means for releasing saidreleasable means at a predetermined point in the upward movement of the platen, means actuated thereafter by the upward movement of the-platen for raising saidmold plates and means associated with said mold side plates for causing them to open when raised to permit the removal of the molded article.

4. In mechanism of the class described, a bottom moldplate, side mold plates interengaging said bottom plate at the edges thereof, releasable means for holding said plates in their lower position, a vertically movable platen, a core depending therefrom, means for raising said platen to pull said core out of the molded article, said platen carrying means for releasing said releasable means at a predetermined point in the upward movement of the Platen, means actuated thereaftg er by the upward movement of the platen for raising said mold plates, means for auto matically releasing said plates from said raising means when the latter has travelled througha predetermined distance, whereby theplates are free to descend by gravity, and means for forcing said slde plates inwardly into molding position as the plates descend.

5. In mechanism of the class described, a

bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof, means for raising sa1d mold plates and si multaneously causmg said side plates to open outwardly in order to permit the removal of the molded article, and means for automatically releasing said plates fromthe raising means when the latter has travelled through a predetermined distance.

6. In mechanism of the class described, a

bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof, a vertically movable platen, a core depending therefrom, means for raising said platen to pull said core out of the molded article, means actuated thereafter by the upward travelof the platen for raising said mold plates and simultaneously causing the mold side plates to open outwardly in order to permit the removal of the molded'article, and means for automatically releasing said plates from said raising means when the latter has travelled through apredetermined distance.

.7. In mechanism of the class described, a bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof, releasable means for holding said plates in the lower position, a vertically movable platen, a core depending therefrom, means for raising said platen to pull said core out of the molded article, said platen carryingmeans for releasing said releasable means at a predetermined point in the upwardmovement of :the platen, means actuated thereafter by the upward movement of the platen for raising said mold plates and 7 simultaneously causing said mold side plates to open in orderto permit the removalof the moldedarticle, and means for automatically releasing said plates from said raising means when the latter has travelled through a predetermined distance, whereby the plates are free to descend by gravity to their operative position. v

8. In mechanism of the class described, a bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof, means for raising said mold plates and simultaneously causing said side plates to open mitwardly-in order to permit the removal of the molded article, means for automatically releasing said plates from the raising means when the latter has travelled through a predetermined distance, whereby the plates are free to descend by gravity to their operative position, and means for cushioning the descent of said plates.

9. In mechanism of the class described, a bottom mold plate, side mold plates inter-engaging said bottomplate at theedges thereof, means-attachedto said bottom plate for raising all of said mold plates, means for guiding' the side plates outwardly as the plates rise and inwardly asthey descend, and means for automatically releasing said plates from the raising means when the latter has travelled through a predetermined distance.

-10. Inmechanism of the class described, a bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof, means attached to said bottom plate for raising all of said mold plates, a fixed frame surrounding said mold plates having inner sidewalls inclined outwardly and upwardly,

interengaging tongue and groove'means between the frame and the side plates for pos1- .tivcly guidlng the latter outwardly as the plates rise and inwardly as they descend, and means for automatically releasing said plates from theraising means when the latter has travelled through a predetermined distance, whereby gravity causes them to return to their lower operative position.

11. In mechanism of the class described, a

bottom mold plate, side mold plates interengaging said bottom plate at the edges thereof,

vertically movable connections attached to gaging said bottom plate att-he edges there- I of and adapted to open in order to free the molded article, releasable means for holding said plates in their closed position, a vertically movable platen, and a core depending therefrom, means for raising said platen to pullsaid core out of the molded article, said platen carrying means for releasing said releasable-means at a predetermined point in the upward movement of the platen.

' 13. In mechanism of the class described, a bottom mold plate, lateral mold plates interengaging said bottom plate at the edges thereof and adapt-edto open in order to free the molded article, a vertically movable platen, a core depending therefrom, means for raising said platen to pull said core out of the molded article, and means for raising said mold plates and causing the lateral mold plates to open outwardly in order to permit the removal of the molded article, said last named means being picked up and carried upward by said first named means during the upward travel of the latter when said'first named means has reached a predetermined position in such upward travel.

In testimony whereof, I hereunto aflix my signature.

PAUL O. GUNKEL.

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